The menus for all buttons and cell entries are activated by right clicking on them. Cells Rows Columns Tableau Columns (above tableau) Highlight Column - changes the background color of every cell in the column for emphasis (toggles on/off); useful for classroom discussions. Delete Column - deletes the column from the tableau; one can continue to pivot in the tableau without errors. Add Column Before - inserts an empty column into the tableau to the left of the given column; this is usually done while constructing the original tableau or modifying a copied tableau (if done after several pivots then further pivots will most likely not be integral); also useful when adding cutting planes for integer optimization problems, but you can add a row simulaneously with the cell button Add Row and Column After instead. Add Column After - inserts an empty column into the tableau to the right of the given column; this is usually done while constructing the original tableau or modifying a copied tableau (if done after several pivots then further pivots will most likely not be integral); also useful when adding cutting planes for integer optimization problems, but you can add a row simulaneously with the cell button Add Row and Column After instead. Fill Column with 0s - enters 0 in each cell of the column; useful for sparse matrix construction or new slack columns. Fill Column with 1s - enters 1 in each cell of the column; useful for setting up an auxiliary problem. Mark as Free Variable - marks the column as corresponding to a free variable by putting a red F on the column button (togges on/of); the F will remain red until a pivot is performed in the column, at which point it will change to (and remain) a green F; useful for remembering to pivot a free variable into the basis and also never to pivot it out.